Off Grid Solar System in Ireland
An off grid solar system lets you power a home, cabin, or farm outbuilding with no connection to ESB Networks. You get complete energy independence, but the system has to handle 100% of your winter demand and cope with short Irish daylight hours. This guide covers off-grid sizing for Irish conditions, component choices, typical costs, and when off grid makes sense compared to a standard grid-tied system.
Quick Answer
An off grid solar system in Ireland typically costs €18,000–€40,000 for a 3-bedroom home, depending on winter demand and battery size. A typical build is 5–8 kWp of panels, 15–30 kWh of lithium (LFP) battery storage, a 5–8 kW hybrid off-grid inverter, and a backup generator for dark winter stretches. Off grid is best for rural cabins, farms, or remote builds where ESB grid connection quotes run €15,000+. For standard homes near the grid, a grid-tied system is cheaper and more practical.
Fact-checked by John Rooney, Solar Energy Editor. Editorial policy
When does off-grid solar make sense in Ireland?
Off-grid solar is the right choice in a narrow set of circumstances. For most Irish homeowners, a grid-tied system is cheaper, simpler, and more practical.
Remote rural builds
ESB Networks connection quotes for remote sites can exceed €15,000–€40,000+ if trenching or poles are required. In these cases, an off-grid system can match or beat the grid connection cost outright.
Cabins and holiday homes
Low-occupancy properties used seasonally (summer cabins, hunting lodges) are a good fit for smaller off-grid systems with modest battery storage.
Farm outbuildings
Milking parlours, pump houses, and sheds far from the main supply can justify off-grid kit rather than long private underground cable runs.
Energy independence
Some homeowners go off-grid for philosophical reasons or to escape rising electricity and standing charges entirely. Expect to pay a large premium for the privilege.
“In almost all cases where a grid connection is available, grid-tied solar with export payments will outperform off-grid economically. Off-grid makes sense when the grid connection itself costs more than the off-grid kit.”
Off grid solar system components
Solar panels (5–8 kWp)
Off-grid sizing is driven by the worst winter week, not the annual average. Expect 14–20 panels on a south-facing roof or ground-mount. See our panel brand comparison.
Battery storage (15–30 kWh LFP)
You need enough storage to carry you through 2–3 cloudy days. LFP chemistry is the standard (BYD HVM, Pylontech, Dyness). See battery storage guide.
Off-grid hybrid inverter
An off-grid-capable hybrid (Victron, Deye, Sol-Ark) or dedicated off-grid inverter. Unlike grid-tied models, it forms its own AC grid, handles load transitions, and integrates generator startup.
Backup generator
Most Irish off-grid systems keep a 5–10 kW diesel/LPG generator for December and January, when solar alone cannot cover demand. Auto-start integration is recommended.
Charge controller (if DC-coupled)
MPPT charge controllers sit between panels and battery in DC-coupled systems. AC-coupled hybrid inverters include this function internally.
Monitoring and load control
Off-grid needs careful load management. Most installs include smart monitoring (Victron VRM, SolisCloud, GivEnergy) and automatic load shedding for high-draw appliances during low-battery periods.
Off grid solar sizing for Irish winters
Sizing an off-grid system for Ireland is harder than grid-tied because December irradiance is roughly 15–20% of June levels. You cannot just scale a grid-tied calculation up.
| Property type | Daily winter demand | Panel size | Battery size | Generator |
|---|---|---|---|---|
| Small cabin / lodge | 3–5 kWh | 3–4 kWp | 10–15 kWh | Optional |
| Seasonal holiday home | 5–8 kWh | 4–6 kWp | 15–20 kWh | Recommended |
| Rural 3-bed home | 10–15 kWh | 6–8 kWp | 20–30 kWh | Required |
| Rural 4-bed + heat pump | 20–30 kWh | 10–15 kWp | 30–50 kWh | Required |
Winter demand figures assume Irish December/January conditions. Households with electric space heating or heat pumps need disproportionately larger systems — electric heating and off-grid solar are a poor pairing unless significant additional insulation is in place.
Typical off grid solar system cost in Ireland
| System size | Panels + battery + inverter | Generator + install | Total installed cost |
|---|---|---|---|
| Cabin (3 kWp, 10 kWh) | €10,000–€14,000 | €1,500–€3,000 | €12,000–€17,000 |
| Small home (5 kWp, 15 kWh) | €15,000–€20,000 | €2,500–€4,000 | €18,000–€24,000 |
| Rural home (7 kWp, 25 kWh) | €22,000–€30,000 | €3,000–€5,000 | €25,000–€35,000 |
| Large rural (10+ kWp, 40 kWh) | €32,000–€45,000 | €4,000–€6,000 | €36,000–€50,000+ |
These figures assume 0% VAT on the solar portion (residential installs) but include VAT on generator and non-solar kit. SEAI grants do not apply to off-grid-only systems — the grant requires a grid connection and microgeneration registration.
Compare this to a grid-tied system of similar generating capacity, which typically costs €7,000–€15,000 installed and qualifies for the SEAI grant and microgeneration export payments.
Off-grid vs grid-tied solar in Ireland
| Factor | Off Grid | Grid-Tied |
|---|---|---|
| Installed cost (similar panel size) | €18,000–€40,000 | €7,000–€15,000 |
| SEAI grant eligible | No | Yes (up to €1,800) |
| Export income | None | 15–32c/kWh (CRU) |
| Backup during cloudy days | Battery + generator | Grid |
| Ongoing standing charge | None | Yes (€250–€350/yr) |
| Maintenance | Battery + generator service | Minimal |
| Best for | Remote sites, no grid | Everyone else |
A hybrid option some homeowners consider is a grid-tied system with EPS (Emergency Power Supply) battery backup. This gives partial backup during grid outages while keeping the SEAI grant and export income benefits of a grid-tied install. See solar battery storage for the EPS setup.
Frequently Asked Questions
How much does an off grid solar system cost in Ireland?
A typical off-grid system for a rural 3-bed home costs €25,000–€35,000 installed, including 6–8 kWp of panels, 20–30 kWh of LFP battery, a hybrid off-grid inverter, and a backup generator. Smaller cabins can be done for €12,000–€17,000. Off-grid systems are not eligible for the SEAI grant.
Can you go fully off grid in Ireland?
Yes, but it is expensive and requires a backup generator for December/January when solar output drops to 15–20% of summer levels. A fully off-grid Irish home typically needs 6–10 kWp of panels, 25–40 kWh of battery, and a 5–10 kW generator to cover dark winter stretches.
Is off-grid solar cheaper than connecting to ESB Networks?
Only for remote sites where ESB connection quotes exceed €15,000–€20,000. For properties within a few hundred metres of an existing line, a standard grid connection plus grid-tied solar will cost significantly less than a full off-grid install.
Do off grid solar systems qualify for the SEAI grant?
No. The SEAI solar electricity grant requires a grid connection and microgeneration registration with ESB Networks. Off-grid-only systems are not eligible. You can, however, apply for the grant on a grid-tied system and add battery storage for backup.
What happens on cloudy days with an off grid system?
Battery storage covers 1–3 cloudy days depending on sizing. Beyond that, a backup generator (typically 5–10 kW diesel or LPG) runs automatically when battery state of charge drops below a threshold (usually 20–30%). Irish December weather often requires several hours of generator use per week.
Can I run an electric car off grid in Ireland?
Yes, but only in summer unless the system is oversized. EV charging adds 2–4 kWh per day for average use, which is manageable on long summer days but adds significantly to winter battery requirements. Most off-grid EV owners run a generator-backed AC charge during the darkest months.
What is the best off grid inverter for Ireland?
Victron MultiPlus-II, Deye SUN series, and Sol-Ark 12K/15K are the most common off-grid hybrid inverters used in Ireland. They support battery backup, generator auto-start integration, and load management. Victron is the premium choice with the longest track record.
Off grid vs hybrid solar: what is the difference?
Hybrid means grid-tied with battery backup — you still have an ESB connection and can import/export. Off-grid means no grid connection at all. Hybrid is cheaper, qualifies for the SEAI grant, and earns export income. Off-grid is only cost-effective when grid connection itself is very expensive.
See also
Related Guides
Sources
- ESB Networks — New connection quotes, esbnetworks.ie
- PVGIS — Solar irradiance data for Ireland, re.jrc.ec.europa.eu
- SEAI — Solar Electricity Grant eligibility, seai.ie
Last updated: April 2026
John Rooney is the founder of Solar Info and has been covering the Irish solar energy market since 2023. He fact-checks all content against official SEAI data and maintains relationships with SEAI-registered installers across Ireland.
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